Getting error: attribute 'unsafeDiscardStringContext' missing while full update on Linux

[x80486]

Describe the bug

I usually do nix-channel --update and nix-env --prebuilt-only --upgrade to upgrade Nix and the installed dependencies. I started getting this error around 4/5 days ago:

unpacking channels...
warning: don't know how to open Nix store 'https://cache.nixos.org/'
created 1 symlinks in user environment
error: attribute 'unsafeDiscardStringContext' missing, at /nix/store/ff8fzv31yydp2qkbvqykjm15zkfs8f3n-nixpkgs-21.05pre281594.6fc2b7ecc2a/nixpkgs/lib/strings.nix:429:13
(use '--show-trace' to show detailed location information)

Steps To Reproduce

1. Install Nix under Arch Linux
2. Update

Expected behavior

To be able to update without error(s).

nix-env --version output

[x80486@uplink:~]$ nix-env --version 
nix-env (Nix) 2.3.10
[x80486@uplink:~]$ uname -a 
Linux uplink 5.10.27-1-lts #1 SMP Tue, 30 Mar 2021 13:22:29 +0000 x86_64 GNU/Linux

[shyim]

Ran into now also 😅

Also nix-env (Nix) 2.3.10
But running Nix inside an Debian docker container

// Edit:

Run now again curl -L https://nixos.org/nix/install | sh and stayed on stable channel

[b0o]

nix-env --upgrade has been failing with this error for me as well these past few days.

$ nix-env --upgrade --show-trace
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels/nixpkgs' does not exist, ignoring
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
error: while evaluating anonymous function at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/impure.nix:15:1, called from /nix/store/0rl36g1wxzf89866h2ic1rwjlc0m8vc9-home-manager/home-manager/default.nix:1:10:
while evaluating anonymous function at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/default.nix:19:1, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/impure.nix:83:1:
while evaluating anonymous function at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:42:1, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/default.nix:122:10:
while evaluating 'dfold' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:60:27, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:136:4:
while evaluating 'go' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:63:18, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:72:13:
while evaluating 'imap1' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/lists.nix:116:14, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:78:30:
while evaluating 'reverseList' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/lists.nix:393:17, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/booter.nix:85:6:
while evaluating anonymous function at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/stdenv/default.nix:7:1, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/default.nix:118:12:
while evaluating 'elaborate' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/default.nix:18:15, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/pkgs/top-level/default.nix:52:17:
while evaluating 'foldl' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/lists.nix:80:20, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/default.nix:149:13:
while evaluating 'foldl'' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/lists.nix:82:16, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/lists.nix:86:8:
while evaluating the attribute 'parsed.abi.assertions' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/default.nix:23:7:
while evaluating 'mkSystemFromString' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/parse.nix:462:24, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/default.nix:23:16:
while evaluating 'mkSkeletonFromList' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/parse.nix:382:24, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/parse.nix:462:49:
while evaluating 'splitString' at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/strings.nix:427:23, called from /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/systems/parse.nix:462:69:
attribute 'unsafeDiscardStringContext' missing, at /nix/store/jpb8f98zm13bcwwycpbr8vclxrdd0l2b-nixpkgs-21.05pre281670.842f900e73c/nixpkgs/lib/strings.nix:429:13

$ nix-env --version
nix-env (Nix) 2.3.10

$ uname -srmov
Linux 5.11.12-1-ck-zen #1 SMP PREEMPT Thu, 08 Apr 2021 11:25:39 +0000 x86_64 GNU/Linux

$ lsb_release -idr
Distributor ID:	Arch
Description:	Arch Linux
Release:	rolling

[leon-barrett]

I believe this is caused by NixOS/nixpkgs#118481 , where nix is being replaced by an "upgrade" to a broken statically-linked nix. While the bug is already closed, the PR hasn't yet rolled out to nixpkgs-unstable. https://nixpk.gs/pr-tracker.html?pr=119317

[adworacz]

So, once this bug is fixed, how to we update to the latest version if the update mechanism is broken? Or perhaps I'm misunderstanding the ramifications of this issue.

[arsfeld]

@adworacz you can rollback with nix-env --rollback, you might have to go a few versions back (at least I had to).

[adworacz]

Excellent, @arsfeld, that's exactly what I needed.

[domenkozar]

If you update nixpkgs-unstable this should be fixed now.

[adworacz]

Confirmed - this is working just fine for me after upgrading.